The functions
archive_entry_uid,
archive_entry_gid,
and
archive_entry_perm
can be used to extract the user id, group id and permission from the given entry.
The corresponding functions
archive_entry_set_uid,
archive_entry_set_gid,
and
archive_entry_set_perm
store the given user id, group id and permission in the entry.
The permission is also set as side effect of calling
archive_entry_set_mode.

archive_entry_strmode
returns a string representation of the permission as used by the long mode of
ls(1).

File flags are transparently converted between a bitmap
representation and a textual format.
For example, if you set the bitmap and ask for text, the library
will build a canonical text format.
However, if you set a text format and request a text format,
you will get back the same text, even if it is ill-formed.
If you need to canonicalize a textual flags string, you should first set the
text form, then request the bitmap form, then use that to set the bitmap form.
Setting the bitmap format will clear the internal text representation
and force it to be reconstructed when you next request the text form.

The bitmap format consists of two integers, one containing bits
that should be set, the other specifying bits that should be
cleared.
Bits not mentioned in either bitmap will be ignored.
Usually, the bitmap of bits to be cleared will be set to zero.
In unusual circumstances, you can force a fully-specified set
of file flags by setting the bitmap of flags to clear to the complement
of the bitmap of flags to set.
(This differs from
fflagstostr(3),
which only includes names for set bits.)
Converting a bitmap to a textual string is a platform-specific
operation; bits that are not meaningful on the current platform
will be ignored.

The canonical text format is a comma-separated list of flag names.
The
archive_entry_copy_fflags_text
and
archive_entry_copy_fflags_text_w
functions parse the provided text and sets the internal bitmap values.
This is a platform-specific operation; names that are not meaningful
on the current platform will be ignored.
The function returns a pointer to the start of the first name that was not
recognized, or NULL if every name was recognized.
Note that every name  including names that follow an unrecognized
name  will be evaluated, and the bitmaps will be set to reflect
every name that is recognized.
(In particular, this differs from
strtofflags(3),
which stops parsing at the first unrecognized name.)